Let's Make Robots!

BEC'S as voltage regulators?

When building a robot a regulated power supply is very important to give the controller a good stable 5 volts. Normally a 7805 or better is used. Which is a lineair supply and is very 'proven technologly'. Except it is not very efficient. When used with a battery pack all the volts above 5 are burnt away.

Solution for this is using a switch mode power supply, (buck and or boost regulators). These have a much better efficiency but are less common and therefore much more expensive. Also the ones I found can delivery less than one amp.

But RC bec's are relativly cheap. But are they capable of delivery a stable voltage?

Units like this: http://www.hobbyking.com/hobbycity/store/uh_viewItem.asp?idProduct=4319

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I love SMPS so much that I've taken to building my own =D
Delivering a stable voltage is always possible using the appropriate smoothing capacitors for the job. If you need really smooth output you can use a small HF filter cap in parallel with a high capacity supercap, although you do have to wait a little for the supercap to charge if the SMPS has been off for a while.
Any chance on getting a writeup of a SMPS design you like? :)
For DIY you mean? Most of mine are simple 2 transistor modules, which offer a nice compromise between low complexity and size, but still with decent efficiency, especially compared to single transistor types. There are many many SMPS designs out there, and it's hard to pull a favourite since they can be tailored to suit the application.
Are you looking to use an SMPS for a particular project or just curious?
BECs are low cost switching regulators. As such, they would be a superior option to standard linear regulators except where noisie limitations are needed. From what I understand, Turnigys are a good working device, some used in multiservo hexapod robots. ANother would be Castle BECs.

I know this isnt a good answer to your question, but I've also been looking at different options for supplying high current low volt which can be useful for example in cases where you need a large amount of servos.

I did look at BEC's used in RC hobby alot, but it seemed like a "cheap" solution to me. I love to learn new things. Therefor I really recommend looking at Oddbot's great tutorials on power supplies, first one is called Once you've decided on batteries, how do you regulate the voltage and the second one which is more relevant to your case and topic; Building the perfect robot power supply. Good luck!

I have shown my design to the engineer at DAGU and we are currently looking at producing it. If all goes well then we may have a switchmode regulator out soon that will work with input voltages up to 30V and deliver from 3.3V to 6V with an output current of about 5A. This will be ideal for running large numbers of servos from 12V and 24V systems.